Get info about resources before publishing

[acouch]

Issue Type

• Bug (https://github.com/interra/catalog-generate/blob/master/CONTRIBUTING.md#bug-reports)
• Feature (https://github.com/interra/catalog-generate/blob/master/CONTRIBUTING.md#feature-requests)

Description

Previewing files requires often requesting info about them via their headers. That doesn't give us enough info due to CORS restrictions. We should CURL the collections that have file previews to get their header info. Socrata files we should not as Socrata and maybe get schema info from there.

Steps to reproduce

(Add link to a demo on https://jsfiddle.net or similar if possible)

Versions

• Node/NPM:
• Browser: